This invention relates to a rectilinear drawing machine for drawing material, especially bars, pipes or sections, with at least two movable drawing cars which are driven on a path, one run being assigned to each drawing car. The invention relates to a process for continuous rectilinear drawing of drawing material by means of a rectilinear drawing machine with at least two drawing cars, the drawing material being drawn by means of at least one drawing car along a run assigned to the drawing car on a path.
Such a drawing machine and such a process for rectilinear drawing of drawing material are known from publication DE 197 03 878 A1.
In the drawing machine disclosed in this publication, on a path, a first drawing car runs, and behind this car, a second drawing car runs, each are each provided with clamps. While one car at a time is drawing, the other is running with increased speed back into its initial position. When the drawing force is transferred from one car to the other, the two cars are synchronously controlled. For this reason, and due to the relatively great length of the clamps which gently grasp the material, in the transfer of the drawing force, from one car to the other, a fall of the drawing speed is avoided.
The disadvantage of the drawing system described in the indicated publication is that invariable lengths of travel are assigned to the individual drawing cars. This results especially in the fact that a continuous feed of drawing material, into the drawing machine, is not possible, or is possible only with great difficulty. So that specifically a continuous feed of drawing material into the drawing machine is possible, the first drawing car must grip the drawing material, spaced so far away from the end of the drawing material that the drawing material, when the first drawing car has reached the end of its run, projects so far into the run of the second drawing car that the second drawing car can pick up and continue to draw the drawing material. This is however very complex, since the drawing material, so that the first drawing car can grasp the drawing material spaced so far away from the end of the drawing material, must either be drawn by hand, relatively far through the drawing die, or the first drawing car in a first cycle grasps the drawing material directly at the drawing die, draws it to the end of its run, then travels back to grasp the drawing material again and to draw it in the direction of the second drawing car.
Therefore it is an object of the invention is to propose a rectilinear drawing machine and a process for operating a rectilinear drawing machine with which continuous feed of the drawing material into a rectilinear drawing machine is easily and quickly possible.